A writer in the local paper--an Arab writer--made the interesting point that, if the terrorists in Iraq had any confidence they had popular support, they would not be using terrorism. They would instead be preparing for the elections, and would be sensitive that killing Iraqi women and children was not going to help their popularity. No, instead, they are working their hardest to prevent the elections. This tells all.
This seems to make it plain that the most likely way to reduce the level of terrorism in Iraq is to hold elections as soon as possible.
More broadly, an insurgent movement that does not have the support of the people is not going to survive long-term, if they cannot seize government quickly and by force. The one danger is ethnic struggle, Sunni against Shia against Kurd, with insurgent movements having support within their ethnic enclave. But Sunni against Shia has not been a serious issue anywhere else in the modern Muslim world to date; so it seems unlikely to happen there.